btrfs send/receive issues

btrfs send/receive issues

[Miguel Negrão]

Hi,

I want to do a backup of a btrfs subvolume from one disk to another
disk, both with btrfs filesystems, using the btrfs  send receive
functionality. I do 

cd /media/miguel/btrfs_backup/
mkdir backups
sudo btrfs send /mnt/@backup2 | sudo btrfs receive /media/miguel/btrfs_backup/backups/

and this works fine, the @backup2 subvolume is created
at /media/miguel/btrfs_backup/backups/. Then I try to send a second
snapshot taken after @backup2 :

sudo btrfs send -p /mnt/@backup2 /mnt/@backup3 | sudo btrfs receive /media/miguel/btrfs_backup/backups/

And I get:

At subvol /mnt/@backup3
At snapshot @backup3
ERROR: open backups/@backup2 failed. No such file or directory

But @backup2 is a subvolume in /media/miguel/btrfs_backup/backups/ 

I'm I doing something wrong ?

best,
-- 
Miguel Negrão
http://www.friendlyvirus.org/miguelnegrao

Re: btrfs send/receive issues

[Josef Bacik]

On Sun, Jun 23, 2013 at 11:41:33PM +0100, Miguel Negrão wrote:
> Hi,
> 
> I want to do a backup of a btrfs subvolume from one disk to another
> disk, both with btrfs filesystems, using the btrfs  send receive
> functionality. I do 
> 
> cd /media/miguel/btrfs_backup/
> mkdir backups
> sudo btrfs send /mnt/@backup2 | sudo btrfs receive /media/miguel/btrfs_backup/backups/
> 
> and this works fine, the @backup2 subvolume is created
> at /media/miguel/btrfs_backup/backups/. Then I try to send a second
> snapshot taken after @backup2 :
> 
> sudo btrfs send -p /mnt/@backup2 /mnt/@backup3 | sudo btrfs receive /media/miguel/btrfs_backup/backups/
> 
> And I get:
> 
> At subvol /mnt/@backup3
> At snapshot @backup3
> ERROR: open backups/@backup2 failed. No such file or directory
> 
> But @backup2 is a subvolume in /media/miguel/btrfs_backup/backups/ 
> 
> I'm I doing something wrong ?
> 

I'm not sure, I just did it and it worked fine for me.  Could you file a
bugzilla at bugzilla.kernel.org and make sure the component is set to btrfs?
Also could you do the send to a file, and then receive from the file so we can
see if its send or receive that's giving you the error and put that in the
bugzilla?  Thanks,

Josef

Re: btrfs send/receive issues

[Miguel Negrão]

Hi Josef,

Mon, 2013-06-24 às 12:21 -0400, Josef Bacik escreveu:
> I'm not sure, I just did it and it worked fine for me.  Could you file a
> bugzilla at bugzilla.kernel.org and make sure the component is set to btrfs?
> Also could you do the send to a file, and then receive from the file so we can
> see if its send or receive that's giving you the error and put that in the
> bugzilla?  Thanks

I've added the bug at https://bugzilla.kernel.org/show_bug.cgi?id=60081

The problem it's on the receiving side, I can create the two files but
then I can't "btrfs receive" the second file, I get the error that it
can't find the directory. I've placed the two files I used for testing
on the bug report, so you can try btrfs receive on them.

thanks,
-- 
Miguel Negrão
http://www.friendlyvirus.org/miguelnegrao